Melofors Jinx

"No matter where Harry went within the castle, the sole topic of conversation was Dumbledore’s flight, and though some of the details may have gone awry in the retelling (Harry overheard one second-year girl assuring another that Fudge was now lying in St. Mungo’s with a pumpkin for a head) it was surprising how accurate the rest of their information was."

The Melofors Jinx (Melofors) is a jinx that encases the victim's head in a pumpkin, although it appears to those watching to transform the victim's head into a pumpkin. The pumpkin can be shattered to free the victim, or can fall apart on its own after a short time.